1. Field of the Invention
Modern internal combustion gasoline engine design is undergoing important changes to meet stricter standards concerning engine and exhaust gas emissions. One major change in engine design is the feeding of blow-by gases from the crankcase zone of the engine into the intake air-fuel mixture at the carburetor just below the throttle plate, rather than venting these gases to the atmosphere as in the past. The blow-dry gases contain substantial amounts of deposit forming substances and are known to form deposits in and around the throttle plate area of the carburetor. Another significant change is the recirculation of part of the exhaust gases to the fuel air intake of the engine. These exhaust gases also have deposit forming tendencies. The deposits caused by the recirculated gases, both blow-by and exhaust gases, restrict the flow of air through the carburetor at idle and at low speeds so that an overrich fuel mixture results. This condition produces rough engine idling and stalling and leads to the release of excessive hydrocarbon exhaust emissions to the atmosphere.
Other types of engines are being designed to meet the problem of exhaust emissions via fuel injection. Both diesel and gasoline engines have been developed which incorporated fuel injection. In these systems, the fuel is delivered in a precise quantity and over a precise time interval into the combustion zone of the engine by means of fuel injectors and the associated valves and pumps. This equipment is designed to very fine tolerances and is susceptible to breakdown with deposite formation. A detergent diesel or gasoline composition is effective for mitigating or preventing this problem.
An object of this invention is to provide a novel detergent additive.
Another object is to provide an improved liquid hydrocarbon composition.
2. DESCRIPTION OF THE PRIOR ART
U.S. Pat. No. 3,075,832 discloses hydrocarbon substituted hydroxy aromatic compounds and their effectiveness as antioxidants for organic materials subject to deterioration in the pressure of air.